Compass



W. C. CUDE Nov. 8, 1949 COMPASS 2 Sheets-Sheefl l Filed Oct. 1, 1945.

ima

Nov. 8, 1949 w. c. cUDE 2,487,044

l coMPAss Filed Oct. l, 1945 2 Sheets-Sheet 2 Patented Nov. 8, 1949 4 Claims.

1.(Granted under fthe act of March 3, -1883, :fas :amendedfApril .30, 1928; y370 -l G. 757) .The invention :described herein may abe manufactured and :used ;.by tor .for the "Government for governmental :.purpofses, yWithout payment ,to me of @any royalty fthereon.

Ilhisinyentionrelates to Compasses and .particul'arly yto eeddy current dampened fcompasses suitable for aday .tand .night .use without artificial light.

.Priorfcompasses,: andi particularly lensatic compasses, :.have employed liquid .,lled capsules and clampf-means :in an eiort lto :minimize the :oscillation period .of ithe needle, :however, ,neither of these...methods have proved Ivery lsatisfactory. These prior ..compasses :'-also -have Abeen .provided with -f-.a few phosphorescent marked .reference points yto assist .fin ytaking reading :at :night .in theabsenceof artificial light, however, .these ifew markings were iins-ufcient I.to give :the f degree "of accuracy required .in :military use.

It is, therefore, anfobjfectof;this.invention to provide an eddy :current dampening compass.

.,Anothertobject of '.thezinvention is to provide a `compass .having ra freely pivoted magnetic needlethat will rapidlycome togrestwwithout the aid .of .liquid dampening ,:means.

This vinvention .has for .another object .means for determining accurate -readingduring 'the day and night without artificial light.

Itisa furtheruobj ect-of this .invention togprovide resilientmountings .toeliminate ynoise `created. by the loosely constructed component parts of the compass.

#A. furtherobj ect of `this linventionis to :provide aompass shielded againstfexternal effects.

'It .is a still furtherobjectof .this invention Ato provide a .compass .that willbe .-simple, easy and economical .in .construction and .eicient and durable .in use.

.The foregoing .and other .objects .and advantagesof' this .invention .willbe more clearly lunderstood 'fromreading theollowingspecication, in conjunction 4with .the drawings forming .a Ypart thereof, wherein:

.Figure .l fa perspective .view .of the .lensatic form fn'f compass :of this invention;

fEigure .2 a .detailed .vertical .section fof 'the jewelmounting;

:Figure 13 `is ra de`tailed vertical section taken on line133 -o'f"Fig. 21, 'parts shown in vvelevation;

-Figure4 is a'plan view of thel'ensatic compass as used for lmaporientation and ireafding;

1=Figure `5 is -fa Iplan view'of "the wrist compass of lthis invention;

Figure 7::is a detailed.vertical-sectiontakencon line l"I--l of `Fig-@parts shown invelevation.

11n .the drawings .wherein like members are given the -samereference number, thefcompass; is illustrated fgenerally vas a case -I containing l,a needle 4capsuleZ yand vrotatable compass cover The .invention is `illustrated in tWo yforms ,'i. e.,'a lensatic compass and vva wrist fcompass. rrllach form .comprises component A.parts -Whch lare interchangeable. Hence, the -following vdetail'edfdescriptionis WrittenAl to ydescribe each ,unitxassembly of .the .two forms, -with .thfe Vunderstanding that parts are interchangeable, .for example, .the needlefcapsule .of one form .may be used. in either case, and the ,same vis .true of the rotatable .com-

pass cover. y

Thefcase I Aof cylindrical cross-.section.isf.pro vided with `a .rotatably-mounted .cover .3'.comprising-a bezelring @having equally =s paced.pe ripheral serrations .6, and `a Y'transparentdisc .-1 secured `to saidring. A .spring .tab ,8 issecured to the .case and ,is provided with aprojection .-9 which engagesthe ,peripheralserrations 6-y of the bezel ring 5.

vThe Wrist compass modication,.see.Figs.-6and 7,. hasahollow vportion A.I I provided .in ,the bottom of the .case .Whichis adapted to receive ya .wrist strap I 2. .This .modification has luminouscalibrations L4 providedbn the under -side ofthe transparent .disc 1 to .provide .durable rotatable indicia. These calibrations .are .in five .degree (5) units .with the .principal compasspoints (90 points) marked with luminous letters yIl and the intermediatemidpoints (45 points) marked .with luminous dots ',I1.

'Thelensatic formof compass has, basicallyythe same case .as the wrist 'form compass. .In `.the lensatic form, however, an arm I8 is lpivotally mounted to vva bracket I9 secured to the rcase I. Thisarm I8 has 'a lens #mounted in the free end thereof, and an extended diametricnarrow aperture 2li between the lensfd and 'free end -of-said arm I8. A closure 2l is pivotally mountedto'the case Idiametricallyfoppositethe arm-I8, andfprovided with aa .diametric Aslot 22 having Aa viinewire sight '2.3 extending longitudinally .therein v'and aligned with the aperture in the:arm .I8. .LA luminousdot .24 is .positioned lat -eachfend of the Wire 23 and in alignment therewith for :night sighting. .The .arm I8 is constructed and .-arranged to fold .across therotatably mounted compass cover 3 and thecase closure 2| yis constructed and arranged to .'fold over the arm I8, the case closure having cut-out yportions {2'6 and .21 .tore-, ceivethe arm I8 and tab 8, respectively.

The transparent disc 'I in the lensatic compass is provided with luminous radial lines 23 and 3!) on the under surface of the disc 'I and spaced 45 degrees (45) apart to assist in setting predetermined angular measurement when used in conjunction with points 45 on the capsule cover 43 and the serrations 6 and tab 8.

The material for the compass case I in each modication is preferably aluminum to shield the compass from external effects, as well as provide a case that is easily stamped from sheets of this material and is durable under conditions of excessive and normally abusive use.

The needle capsule 2 comprises a copper cup 3i having a conical pivot 32 secured to the bottom thereof and extending inwardly in axial alignment therewith. The cup may be of other electric conductive material, and also may be in the form of a ring. The pivot 32 supports a jewel mounted magnetic needle 33 having a length slightly less than the diametric measurement of the cup 3l for maximum flux cutting by the cup and to accommodate slight tilt angles, such as 8 to 10 degrees. The jewel mounting comprises a non-magnetic setting 34, adapted to receive and retain a jewel 36, usually glass, fitted into the setting. The jewel has a conical complement recess 3'I which receives the conical pivot 32, and registering with the recess 3'I in the jewel is a similar conical complementary recess 35 in the setting 34 having an annular shoulder 33 to which is tted a gasket 4 I, such as rubber or other resiilent cushioning material. This gasket 4I is positioned to contact the pivot 32 when the compass is tilted a predetermined angle of 8 to 10 degrees. The jewel mounting is capped with a resilient cushion 42, preferably constructed of rubber. The capsule is closed with a transparent cover 43, which is fitted close enough to the jewel mounting cushion 42 to prevent the mounting falling off the pivot 32 when the case is inverted. The cover 43 is provided with an annular shoulder 48 which contacts the cup 3i to x the distance between the cover 43 and mounting cushion 42.

In the wrist form compass, the transparent capsule cover 43 has a luminous arrow 44 diametrically positioned thereon which functions as a fixed index in demarking angular measurements; and the lensatic compass has the four principal compass points marked with luminous dots 45 and a radial line 46 terminating in one of said dots 45 which functions as a xed index. The lensatic form, also, has a transparent dial G supported by and secured to the needle 33. The dial 56 has the principal points 5I of the compass luminously marked and a luminous radial pointer 52 terminating in the north marking, and degree and mil scales marked with thin black lines 53 and 54, respectively, which function as rotatable indicia.

The lensatic form has the interior of the cup 3I coated with a light reflective material such as White enamel, and a luminous segment 5B provided therein to assist in night reading. The luminous segment being positioned in the manner illustrated and described, causes the black markings 53 and 54 on the transparent dial to be legible at night.

In manufacturing the component parts of the Compasses and assembling the parts into a complete structure, the various dimensions are such that the parts'of one form of the compass may be employed in the other modifications thereof.

For the sake of clarity, each assembly will be described as illustrated in the drawings.

The lensatic case I is stamped from sheets of aluminum and assembled with the'lens arm I8 and closure 2l. The needle capsule 2 is assembled with the cup 3I conical pivot 32, jewel bearing supported needle 33 and'cover 43, care being taken to position the cover 43 such that the radial line 46 bisects the luminous segment 5E in the cup 3l. The capsule 2 is then inserted in the case and cemented thereto, with the capsule cover radial line 43 aligned with the case sighting aperture 20 and wire 23. The bezel ring 5 is then snapped into the case where it is held by coacting lugs on the case and ring and the spring tab 3.

The assembly of the wrist compass form is similar to that of the pocket modification. However, the capsule cover luminous diametric arrow 44 is aligned with the wrist strap I2.

In operation, both types of Compasses are used to determine horizontal angular measurements in a clockwise direction from magnetic north. The lensatic type compass is held with the lens 4 focused on the dial 55. The line of sight of the eye being through the lens 4 to the dial 5I! for angular readings; andthrough the slot 20 in the lens arm I8 to an object aligned with the closure wire 23 for objective identity. The compass is used frequently at night when it is both dangerous and awkward to employ articial light for reading. The luminous segment 56 renders the black lines and numbers on the dial 50 legible, and the luminous dots 24 in the case closure 2| forms a sighting reference in lieu of the sighting wire 23 used in daylight, In theA pocket modification, the compass is assembled with the diametric luminous arrow 44 aligned with the Wrist strap I2 for convenience in sighting along the longitudinal axis of the arrow.

The serrations on the bezel ring 5 being spaced to turn an angle of 3 degrees for each serration, and the and 45 degree points being luminously marked, it is possible to set the compass to the nearest 45 degrees and turn the bezel ring to add or subtract 3 degrees for each serration until the desired point is located within a degree. f

Having thus described myinvention, what I claim as new and wish to secure by Letters Patent is:

1. A compass comprising a case, a copper cup inserted insaid case, a pivot supported by said cup and extending inwardly in axial alignment therewith, a bearing supported by said pivot, a setting of non-magnetic material supported by said bearing, an annular sound cushioning gasket supported by said setting and surrounding said pivot, and a sound cushioning cap positioned over said setting, a magnetic needle supported by said bearing setting, a transparent cover for said cup, a rotatably mounted transparent cover for said case, and coacting fixed and rotatable indicia respectively located on said first-mentioned transparent cover and fixed relative to said needle, and adapted to define angular measurements relative to the normal pointing of the magnetic needle.

2. A compass comprising a case, a copper cup inserted in said case, a pivot supported by said cup and extending inwardly in axial alignment therewith, a bearing positioned on said pivot, a

setting for said bearing and surrounding said pivot, a resilient sound dampening gasket'at-- tached to said setting and positioned to Contact .5 said pivot when the setting is tilted at an angle, a magnetic needle secured to said setting and having a length slightly less than the diameter of said cup, a transparent dial supported by said needle and having an opaque angular measurement scale positioned thereon, a luminous segment in said cup rendering the scale portion thereover legible in the absence of light, a resilient sound dampening cap for said bearing and setting, a cover for said cup having a fixed index cooperating with said dial scale to demark angular measurements from the normal pointing of the magnetic needle, and a transparent cover for said case.

3. A compass comprising a case, a copper cup inserted in said case, a pivot supported by said cup and extending inwardly in axial alignment therewith, a bearing positioned on said pivot, a setting for said bearing and surrounding said pivot, a gasket secured to said setting and positioned intermediate said setting and pivot, a magnetic needle secured to said setting, a transparent cover for said cup, a diametric luminous fixed index on said cup cover, a transparent case cover mounted on said case and rotatably movable in fixed angular distances, and angular measurement indicia provided on said case cover, adapted to dene intermediate divisions on the index of said cup cover.

4. A compass comprising a case, a copper cup inserted in said case, a pivot supported by said cup and extending inwardly in axial alignment therewith, a bearing supported by said pivot, a setting of non-magnetic material supported by said bearing, an annular sound cushioning gasket supported by said setting and surrounding said pivot, and a sound cushioning cap positioned over said setting, a magnetic needle and a dial supported by said bearing setting, a transparent cover for said cup, a fixed pointer on said cover, a rotatably mounted transparent cover for said case, and rotatable indicia located on said dial cooperating with said fixed pointer to demark angular measurements relative to the normal pointing of the magnetic needle.

WILLIAM C. CUDE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,003,179 Faus May 28, 1935 FOREIGN PATENTS Number Country Date 1,818 Great Britain Feb. 4, 1915 14,083 Great Britain June 18, 1913 29,677 Great Britain Dec. 21, 1910 445,312 Great Britain Apr. 7, 1936 782,576 France Mar. 18, 1935 

